The broad objectives are to continue our studies on the immune response (Ir) to synthetic polypeptide polymers in highly inbred chickens and other birds with hopes of obtaining information on (1) the relation of immune responsiveness to related polymers to the major modifying genes involved in immune responsiveness; (3) the cellular requirements for immune responsiveness; (4) in collaboration with Dept. of Avian Sciences, University of California, Davis, to develop congenic chicken lines with hopes of mapping MHC genes; and (5) to characterize avian allotypes structurally and genetically.